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Ginette Ratovo Jean‐Pierre Souchard Pascale Urizzi Yvon Coulais Franoise Nepveu Etienne Hollande 《应用有机金属化学》2004,18(1):1-8
Pancreatic cancer has an extremely poor prognosis, due, in part, to lack of methods for early diagnosis. The present study was designed to evaluate the potential of labeling low‐density lipoprotein (LDL) with a radionuclide using a lipid chelating agent, bis(stearylamide) of diethylenetriaminepentaacetic acid (L), to detect pancreatic tumors by gamma‐scintigraphy. Previous studies indicated that the difficulty of visualization of pancreatic tumors was due to their poor vascularization. This study compares the ability of two radiotracers, 111In–L–LDL and 153Gd–L–LDL to target highly vascularized rat pancreatic tumors (AR4‐2J) implanted in nude mice. Biodistribution studies showed that the tumor uptake of 111In–L–LDL and 153Gd–L–LDL tracers was twofold and fivefold higher respectively than with the controls (111In citrate and 153Gd citrate respectively). These tracers would thus be suitable for scintigraphic imaging. We show here that LDL could be employed as a delivery system for tracers such as 111In or 153Gd when these two radionuclides are complexed by a lipid‐chelating anchor, and that 111In–L–LDL and 153Gd–L–LDL enabled better visualization of the pancreatic tumor tissues, with a better result with 153Gd–L–LDL. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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The previously reported (J. Mol. Spectrosc.68, 195–222 (1977)) study of the CH3D spectrum occurring at 1033–1270 cm?1 which was mainly concerned with the ν6 fundamental has now been extended to cover the region 1270–1420 cm?1. In all, 342 transitions belonging to the ν3 band are now assigned. Both the ν3 and ν6 bands are processed simultaneously taking into account of the Coriolis interaction between them, and the fitting of all the experimental data led to 21 significant spectroscopic constants for the states v6= 1 and v3 = 1 of CH3D. 相似文献
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Ginette Gauyacq 《Discrete Applied Mathematics》1997,80(2-3):149-160
We present a technique for building, in some Cayley graphs, a routing for which the load of every edge is almost the same. This technique enables us to find the edge-forwarding index of star graphs and complete-transposition graphs. 相似文献
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Rapid postcolumn methodology for determination of paralytic shellfish toxins in shellfish tissue 总被引:1,自引:0,他引:1
Rourke WA Murphy CJ Pitcher G van de Riet JM Burns BG Thomas KM Quilliam MA 《Journal of AOAC International》2008,91(3):589-597
A rapid liquid chromatographic (LC) method with postcolumn oxidation and fluorescence detection (excitation 330 nm, emission 390 nm) for the determination of paralytic shellfish toxins (PSTs) in shellfish tissue has been developed. Extracts prepared for mouse bioassay (MBA) were treated with trichloroacetic acid to precipitate protein, centrifuged, and pH-adjusted for LC analysis. Saxitoxin (STX), neoSTX (NEO), decarbamoylSTX (dcSTX), and the gonyautoxins, GTX1, GTX2, GTX3, GTX4, GTX5, dcGTX2, and dcGTX3, were separated on a polar-linked alkyl reversed-phase column using a step gradient elution; the N-sulfocarbamoyl GTXs, C1, C2, C3, and C4, were determined on a C-8 reversed-phase column in the isocratic mode. Relative toxicities were used to determine STX-dihydrochloride salt (diHCl) equivalents (STXeq). Calibration graphs were linear for all toxins studied with STX showing a correlation coefficient of 0.999 and linearity between 0.18 and 5.9 ng STX-diHCI injected (equivalent to 3.9-128 microg STXeq/100 g in tissue). Detection limits for individual toxins ranged from 0.07 microg STXeq/100 g for C1 and C3 to 4.1 microg STXeq/100 g for GTX1. Spike recoveries ranged from 76 to 112% in mussel tissue. The relative standard deviation (RSD) of repeated injections of GTX and STX working standard solutions was < 4%. Uncertainty of measurement at a level of 195 microg STXeq/100 g was 9%, and within-laboratory reproducibility expressed as RSD was 4.6% using the same material. Repeatability of a 65 microg STXeq/100 g sample was 3.0% RSD. Seventy-three samples were analyzed by the new postcolumn method and both AOAC Official Methods for PST determination: the MBA (y = 1.22x + 13.99, r2 = 0.86) and the precolumn LC oxidation method of Lawrence (y = 2.06x + 12.21, r2 = 0.82). 相似文献
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Abstract— The absorption, fluorescence and phosphorescence spectra along with the phosphorescence decay function of indole perturbed by various amounts of halocarbons have been studied in a 1:1 ethanol-ether glass at 77 K. For carbon tetrachloride. chloroform, halothane and methylene chloride used as quenchers. the biexponential nature of the phosphorescence decay prompted us to assume the existence of a triplet state complex (exciplex) between indole and the halocarbons. On the other hand. propyl bromide gives rise to a non-exponential decay and to an increase in the phosphorescence intensity suggesting the occurrence of a normal external spin-orbital coupling interaction between indole and the propyl bromide molecule. 相似文献
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Belkacemi Khaled Turcotte Ginette Halleux Damien de Savoie Philippe 《Applied biochemistry and biotechnology》1998,(1):441-462
Lignocellulosic materials derived from forages, namely timothy grass, alfalfa, reed canary grass, and agricultural residues,
such as corn stalks and barley straw, were pretreated using ammonia fiber explosion (AFEX) process. The pretreated materials
were directly saccharified by cellulolytic enzymes. Sixty to 80% of theoretical yield of sugars were obtained from the pretreated
biomasses. Subsequent ethanolic fermentation of the hydrolysates byPachysolen tannophilus ATCC 32691 resulted in 40-60% of theoretical yield after 24 h, based on the sugars present in the hydrolysates. The uptake
of sugars was not complete, indicating a possible inhibitory effect onP. tannophilus during the fermentation of these substrates. 相似文献
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Novel thermal transformations of (+)-pin-2-en-9-al 1 and (+)-9-methyl-pin-2-en-9-one 3 by [3,3] sigmatropic mechanism to allyl vinyl ethers 2 and 4 are described. The ether 4 may undergo further rearrangement in an acid-catalysed step to the (-)-2.6-dimethylbicyclo[3.3.1]non-6-en-2ones (5 and 5'). Formation of the bicyclic ketones (+)-5 and 5' of opposite absolute configuration occurs by [3,3] sigmatropic rearrangement of the trimethylsilyl enol ether of 3 and hydrolysis. The proposed mechanism is confirmed by studying the deuterated ketone d3?3. 相似文献